Streak-ribbed product and process of making same



Patented Sept. 25, 1928.

UNITED STATES 1,685,355 PATENT OFFICE.

GARLETON ELLISQOF MON'ICLAIR, NEW JERSEY, ASSIGNOR 'IO ELLIS-FOSTER COI-IANY, A. CORPORATION OF NEW JERSEY.

I STREAK-REBED PRODUCT AND PROCESS OF MAKING sum.

No Drawing.

I This invention relates to sheeted material or plate and various moldedor shaped products of novel appearance and to the process of makingsame. In a co-pending application Serial No. 742,719, I have describedthe formation-of striated molded articles by pressing togetherresin-impregnated multi-colored fragments of paper. In the presentinvention it is an object to secure striated products the striations ofwhich are of a moreregular or uni form character than obtained by theprocess set forth in said application. Also in some cases I desire toobtain banded eifectsor parallel striation including the peculiarstriped elfect employed in imitating ivory.

In carrying'out my invention I impregnate paper or other tissue whichpreferably should be unsized employing as the impregnating medium aresin preferably a synthetic resin in the mold when hot pressed atelevated temperatures. Phenol formaldehyde resins may be employed insome cases for this'operation especially for darker colors but generallyspeaking I prefer a light colored base in which the striations appearand the phenol formaldehyde resins are therefore not suit-' able for usein this way because of discoloration bylight. p ,1

A satisfactory resin fonthe purpose is however made by treatment of ureawith formaldehyde. Such material may be obtained in its initialstage ofconversion in the 'form of an aqueous syrup with which the paper may beimpregnated. The urea formaldehyde resin maybe used by itself or it maybe incorporated with other resins to secure a fluxing efl'ect. One.resin which is satisfactory for this purpose is that obtained byreacting on acetone with formaldehyde in the presence of an alkalinecatalyst. A mixture of say one part of the acetone formaldehyde resin tothree or four parts of the urea formaldehyde resin may be employed toadvantage.

The tissue employedmay be ordinary tissue paper or parchment paper-orheavily calen-.

dered imitation parchment paper known as glassine paper. Heavier formsof paper such, as thin blotting paper may be employed in.

some cases also muslin or other thin cloth. Generally speaking I preferto obtain a translucent product and the employment ofheavy paper whichcannot be thoroughly impregnated to obtain translucency is objectionableApplication filed October 25, 1924. Serial No. 745,987.

having the property of hardening or setting REISSUED for the purpose.The paper may be dyed different colors or the resin solution may beemployed with different dyes or pigments or both the paper and the resinsolution may be colored. Sheets of one color are piled one on anotheruntil the requisite thickness of that color is secured and then othersheets of a di'fl'erent color are piled thereon. In this way there maybe built up a pressboard of any desired thickness. This is exposed to apressure of 2000 pounds per square inch in a press at 125 C. for aperiod of 10 minutes or more depending on'the thickness of thepressboard. After cooling in a cold press a laminated product havingdifferently colored strata is obtained. The pressboard is then sawed orcut transversely into small strips and these are placed togetheredgewise in the mold and re-pressed. In this way the positionof thestripes or strata is reversed and the surface of the pressed article nowshows striations in parallel bands extending across its surface andthrough to the opposite side.

This method may be continued,'the article obtained by the secondpressing being again out and-pressed or folded and pressed to obtainstill more striking effects.

The strips referred to above before pressing ma be dipped in asolutionof the urea formal ehydesyrup employed for impregna' tion (with orwithout acetone formaldehyde resin) in order to cause the surfaces ofthe strips tobett'er adhere on the second pressing.

Since in the first pressing, which preferably may take place at 110125C., a slight amount'of setting may occur it is desirable to carry outthe second pressing at a somewhat higher temperature, say 130 C. Howeverif discoloration occurs at that temperature a longer periodat a lowertemperature may be.

employed.

The banded ing of appearance due to the fact that the striations orbands formed by the dark lorsheets thus obtained are striked-paper showa vigorous contrast alon 'de like Instead of pressing in the form of a asheet the material may be molded into various shapes such as receptaclesof various kinds, handles and varlous ornamental articles.

Further b having the striations narrow and of a l g t brown tonealternating, with no broader bands of the color of ivory an efi'ectquite similar to ivory may be obtained.

A description of the method of making the urea formaldehyde resinintermediate syrup and the acetone formaldehyde resin and'theirincorporation follows.

I Example 1.- -Urea resin syrup: 30 parts of urea are dissolved in 120parts of aqueous formaldehyde and 3 parts of phthalic anhydride areadded to the solution. The mixture is then slowly and gradually heated,the temperature being around 80-90 0., in a flask connected with an aircondenser or a.w'atercooled reflux condenser. The heating is continueduntil the contents of the flask become clear and water white. The syrupso obtained is then cooled and stored. This syrup usually contains fromto 55 per cent of solids. It can'be diluted with water to a 25 or 30 percent solution without any danger of precipitation.

Example 2.Composite product: 7 5 parts of urea are dissolved in 325parts of aqueous formaldehyde and to this 25 parts of molten phenol and10 parts of phthalic anhydride are added. The mixture is then verygradually brought to slight boiling and is maintained at this pointuntil the milky solution which is first formed gradually becomes clearand water white. Extensive boiling as well as sharp raising of thetemperature should be avoided in order to prevent the possibility ofcoagulation of the syrup. To the clear syrup so obtained while stillwarm a small amount (2 or 3 per cent) of alcohol is added. Thisprevents-the syrup from turning milky on cooling Example 3.Acetone resinsolution: 30 parts of acetone are mixed with 225 parts of aqueous 40 percent formaldehyde in a large round bottom flask. 26 grams of per centaqueous solution of pure sodium hydroxide are then added and the flaskis allowed to stand in the cold. In a short time an energetic exothermicreaction is taking place and a sli htly yellowishgummy resin separates.on t e bottom. The reaction is checked at thls point by adding a largeamount of cold water inorder to obtain an alcohol soluble resin.Thewater layer is then decanted and the resin is washed with water freefrom caustic and finally is dissolved in an amount of alcohol so as toform a 30 per cent solution.

The method of preparing thh mixed complex'solution is as follows:

(A) A 50 per cent solution of either syrup #1 or composite resin #2 ismixed withan equal weight of 30 per cent alcoholic solution of acetoneresin #3 and the mixture used for mpregnation. Y

(B) he same 50 per cent urea syrup #1 could be mixed with 30 per centsolution of other light colored products soluble either in water oralcohol, as for example a glycerol tartrate, citrate or phthalate.

lmpregnation of paper may be carried out simply by soaking, or passingthe paper through a bath of the solution. Or pressure and vacuummethods, known to the impregnation art, may be employed in some case.

' What I claim is 5- 1. A process. of making a streak-ribbed sheetmaterial or plastic product which comprises impregnating sheets of thinpaper with a synthetic resin comprising urea resin, superposing sheetsof different colors, hotpressing to weld the sheets together to aedgewise in a hot press and pressing to weld the strips together to forma streak-ribbed or variegated partially translucent product.

3. A process of making a streak-ribbed sheet material or plastic productwhich comprises impregnating sheets of thin paper with a syntheticresin, superposing sheets of different colors, hot-pressing to weld thesheets together to a thicker sheet or block, cutting such pressedmaterial transversely to make thin strips, assembling the stripsedgewise in a hot press and pressing to weld the strips together to forma streak-ribbed or variegated partially translucent product.

4. A process of sheet material or plastic product which comprisesimpregnating sheets of paper with synthetic resin comprising urea andacetone resins, superposing sheets of diflerent colors, hotpressing toweld the sheets together to a thicker sheet or block, cutting suchpressed material transversely to make strips, asembling the stripsedgewise in a hot press and pressing to weld the'strips together to forma streakribbed or variegated partially translucent product.

5. A process of making a streak-ribbed sheet material or plastic productwhich com- "prises impregnating sheets of thin paper of difierent colorswith a synthetic resin comprising urea resin, superposingjsuch sheets ofdifferent colors, hot-pressing to weld the sheets together to a thickersheet or block, cutting such pressed material transversely to makethin'strips, assembling the strips edgewise in a hot press and pressingto weld the strips together to form a streak-ribbed or variegatedpartially translucent product.

6. A process of making a streak-ribbed making a streak-ribbed sheetmaterial or plastic product which comprises impregnating sheets of paperwith synthetic resins of different colors, superposing the resultingsheets of different colors, hotpressing to weld the sheets together to athicker sheet or block, cutting such pressed material transversely tomake strips, assembling the strips e gewise in a hot press and pressingto Weld t e strips together to form a streak-ribbed or variegatedpartially translucent product.

7. A process of making a streak-ribbed sheet material or plastic productwhich c0111- prises impregnating sheets of paper of different colorswith synthetic resins of different colors, superposing such sheets ofdifferent colors, hot pressing 'to weld the sheets together to a thickersheet or block, cutting such pressed material transversely to make thinstrips, assembling the strips edgewise in a hot press and pressing toweld the strips together to form a streak-ribbed orvariegated partiallytranslucent product.

8. A process of making a. streak-ribbed sheet material or plasticproduct which comprises impregnating sheets of paper wit-h a syntheticresin comprising urea resin, superposing sheets of different colors, hotpressing to weld the sheets together, cutting such pressed materialtransversely to make strips, assembling the strips edgewise, and hotpressing to weld the strips together at a tempera.- ture higher thanthat used in the first hot pressing step.

9. Streak-ribbed translucent pressboard containing a light coloredsynthetic resin.

10. Streak-ribbed translucent pressboard containing urea resin.

11. Streak-ribbed translucent pressboard containing urea and acetoneresin.

CARLETON ELLIS.

